Tool dressing form



June 30, 1931. F. SWAN 1,812,025.

TOOL DRESSING FORM Filed Jan. 8, 1929 2 Sheets-Sheet 1 INVENTOR Ffe$ J an I A TTORNEY June 30, 1931. F. SWAN 1,812,025

TOOL DRESSING FORM Filed Jan. 8, 1929 2 Sheets-Sheet 2,

11v VENTOR aafiffj A TTOR/VEY Patented June 30, 1931 umrsasrarss v PAT NT fortce FRED SWAN, or WIcI- ITA, KANSAS, nssrenon; TO THE BRIDGEPORT' MACHINE corr- IPANY, OF WICHITA, KANSAS, A COBI'ORATION' OF DELAWARE TOOL DRESSING FORM Application filed January 8,1929. Serial to. 331,141. f

This invention relates to tool dressing forms'and it1is' particularly designed as a form for dressing the cutters of underreamers such'as are used in oil Wells.

The faces of underreamer cutters, particularly of the rotary type, become worn'and have to be frequently redressed. In order "to-obtain the best results, the curvature of the outer face of the underreanier should have a definlte conformation. For example, thearc of the-curve of the outer face of the underreamer cutter should conform to the arc of the curve of the wall of the hole when it is underreamed. These tools of necessity nust be dressed inth'e field so I have provided a simple inexpensive accurate and easily operated tool dressing form by means of which the tool (for example, the underreamer cutter) can be conveniently, expeditiously, and accurately redressed in a most convenientmanner.

In the drawings, Fig. l is a perspective View of a tool dressing form constructed in accordance with my invention showing the underreamer cutter in place and the gage ring ready to be applied.

Fig. 2 is a top plan view of the underreamer cutter dressing form with the cutter in position to be dressed.

Fig. 3 is a view of a drift key for the yoke securing key.

Fig. l is a side view of the tool dressing form and Fig. 5 is a perspective view of the cutter to be dressed.

The dressing form is shown as comprising a casting having a base 1, a standard 2 and an anvil head or form 3. The standard is reinforced by ribs 4, 5 and 6. The head 3 is provided with a cutter engaging portion 7 which snugly fits the recess 8 of the cutter 9. Carried by the head 3 is an upstanding projection 10 having a gage face 11, the curvature of which conforms to the desired curvature of the face 12 of the cutter 9. WVhen the projection 7 is in the recess 8 of the cutter 9, the reins 13 and 14 straddle the standard and the cutter is held rigidly to the anvil or head by a U-shaped clamping member 15, constituting in effect a yoke consisting of the curved intermediate cross bar 16and the two side bars 17 and 18. The side bars are provided with alining slots'19 and 20 which a slot 24 through which a-locking key 25 (see Fig. 3) can be driven to lock the key rigidly to the casting when the cutter is being held thereon. This prevents the parts from working loose during'the dressing operation. At the rear portion of the anvil is --a T-shaped extension 26having diametrically, oppositely disposed projecting portions 27' and 28 provided with spring seats 29 and 30 for the springs 31 and'32 which are adapted to bear againstthe ends of the side bars 17 and 18 o f'the yoke to tend to release it from clamping position when the key 22 is eased off and since the springs bear against the ends of the bars off center, the clamping. yoke will be slightly tilted during its releaseto effect a positive disengagement from the cutter which has been clamped between the bar 16 and the portion 7'of the headl At the base of the portion 7 is an outwardly and upwardly inclined stop or cutter support 33 upon which the Web 34Lrests and'at the angle source so that dangerof extraneous matter building up at the angle of intersection will be eliminated.

l Vhen the parts are assembled, the key 25 will be removed, the draw' key 22 will be of intersection of the table-like projection and the front face of-the projection 7 'is 'a relief groove 35 to receive any accumula 'tions from the cutter 9 or from any other eased off so that the yokecan be moved I forward, then the cutter 9 WlllbB placed on the anvil head of the casting. The draw key 22 will now be driven home to cause the clamping yoke to clamp the cutter between the bar-6 and the front face of the projection 7 ,"then the drift key 25 will be-driven' inthe 'slot'24. The tool dresser will now proceed to dress the face of the cutter in the usual way, from time to time applying the ring gage 36 over the gage face 11 and over the front face of the cutter until the face 12 of the cutter is cut on the proper arc, then the key 25 can be removed, the draw key 22 can be eased off and the cutter removed. The dressing form will now be ready to receive another cutter to be dressed, it being understood that accumulations in the relief groove 35 are to be removed from time to time.

hen the tool is being dressed, the. casting is thrown over until it rests on projecting portions 27 and 28 and the foot 27. It is then in a horizontal position. hen the key 22 is released, the springs 31 and 32 being off center with respect to the ends of the yoke will push it upwardly and outwardly so as to release the tool, otherwise the yoke would still tend to clamp the tool to the casting.

From the foregoing it will be apparent that the tool dressing form is rigid in construction, well adapted to stand hard usagesuch as it, will encounter in the'oil fields and that it will effectually clamp the cutter in a rigid manner while it is being dressed.

\Vhat I claim and desire to secure by Letters Patent is 1. A tool dressing form comprising a casting, a tool engaging portion on the casting, a tool receiving rest at an angle to the face of the tool engaging portion, the casting having a relief groove at the angle of intersection of the outer face of the tool engaging portion and the tool rest and means for clamping the tool to the casting.

2. A tool dressing form comprising a cast ing having a head, means for fastening the tool to the head and a gage receiving member having a face, the curvature of which is equal to the curvature at which the tool is to be dressed.

3. A tool dressing form comprising a casting, a head on the casting, a tool engaging projection on the head, a tool rest on the head adjacent to the tool engaging projection, a gage receiving member carried by the head, a yoke for clamping the tool to the head having side bars provided with slots to aline wit-h a slot in the casting and a tapered draw key passing through the slots to draw the yoke into clamping engagement with the casting.

4. A tool dressing form, comprisinga casting, having a tool receiving portion, a yoke for clamping the tool to the casting, a draw key for drawingthe yoke toward the casting to clamp the tool thereto, spring seats, and springs mounted on the spring seats bearing against the ends of the yoke to urge the yoke in tool releasing position.

5. A tool dressing form, comprising a casting, having a tool receiving port-ion, a yoke for clamping the tool to the casting, a draw key for drawing the yoke toward the casting to clamp the tool thereto, spring seats, and springs mounted on the spring seats bearing against the ends of the yoke off center to urge the yoke in tool releasing position.

6. A tool dressing form, comprising a. casting, having a base and a tool receiving portion, means for clamping the tool to the casting and a rest spaced from the edge of the base and co-operating with the edge of the base to support the casting'at right angles to the base.

7. A tool dressing form, comprising a casting, having a tool receiving portion, a yoke for clamping the tool to the casting, a draw key for drawing the yoke toward the casting to clamp the tool thereto, spring seats,

springs mounted on the spring seats bearing agalnst the yoke to urge the yoke 1n tool releasing position and a drift key passing through the draw key to hold the draw key.

in position to maintain the yoke in clamping position.

8. A tool dressing form, comprising a castmg, having a tool receiving portion, a yoke for clamping the tool to the casting, a draw key for drawing the yoke toward the casting to clamp the tool thereto and a drift key passing'through the draw key to prevent longitudinal movement of the draw key.

In testimony whereof I afifix my signature.

FRED SWAN. 

